Meter reading systems for reading utility usage at a utility usage registering device are well known. An example is disclosed in the Sears U.S. Pat. No. 4,463,354 entitled Apparatus for Communicating Utility Usage Related Information from a Utility Usage Location to a Portable Utility Usage Registering Device. Other types of utility meter reading systems are known which transmit via radio frequency or which transmit to a central location via phone lines or other hard wired devices.
The prior art suffers from the disadvantage that the meter reading devices are costly and costly installation and hard wiring may be required.
In the prior art radio transmitter meter reading systems, a meter reader would transmit a signal which would "wake up" a particular meter transponder or a group of meter transponders to cause the transmitter at the meter to send back meter information, such as account numbers, utility usage, etc. Such a system utilizes a receiver at the meter, which is ON continuously to receive the "wake up" signal. Receivers add to the cost of the device and increase the energy consumption, which is particularly disadvantageous when battery power is required. Elimination of a receiver at the meter location renders the utility usage registering device much less expensive than the prior art devices and reduces battery drain.
It is desirable to provide an inexpensive apparatus and method for communicating utility usage information to a utility usage registering device which utilizes low cost components and which is still operable to transmit over a fixed, accurately controlled frequency which is assigned by the FCC.
It is known for prior art utility meters to include tamper and leak detectors. However, some of the prior art detectors are actuated to a predetermined condition upon the occurrence of a tamper or leak event and must be reset to register the next event. Such a tamper or leak device cannot be reset except if a receiver or a manual reset means is provided at the meter module.
In addition, it is desirable to provide a method and apparatus for communicating utility usage information from a plurality of utility usage locations to a single utility usage registering device where CLASH (or the reception of simultaneous transmissions) among the plurality of meter modules is minimized by controlling the sensitivity of the receiver and transmitting the utility usage information at a pseudo-random interval.